Pseudo-keriothecal wall texture in Cenomanian Nezzazatina Kaminski 2004: Implications for the higher rank classification of agglutinated foraminifera

Abstract

The current classification of agglutinated benthic foraminifera is based on gross test morphology, and wall structure (including cement composition). Referring to the suborder Nezzazatina Kaminski with the nominal type genus Nezzazata Omara, the wall structure is defined as simple (= not canaliculate), non-lamellar, and microgranular in current taxonomic classifications. The evidence of a pseudo-keriothecal wall structure observed in nezzazatid specimens (Nezzazata, Rabanitina?) from the Cenomanian Sarvak Formation of SW Iran challenges the diagnosis of the genus Nezzazata and the higher supra-generic ranks. The new observation rehabilitates Omara, originally defining the wall of Nezzazata as finely perforate, doubted by subsequent workers and therefore not being included in any classification. Pseudokeriothecae have so far been recorded for example from the orders Loftusiina Kaminski (Coskinolinidae, Biokovinidae, Charentiidae) and Textulariida Delage and Hérouard (Chrysalinidae) in some families. It is herein reported also from the order Nezzazatina, family Nezzazatidae respectively thus documenting that this type of wall microstructure appears to be of secondary taxonomic importance.